In order to support the Superfund Program, statistical Core C will be expanded to contribute to all proposed projects and the new laboratory Core D. The purposes of Core C are to: 1) provide project investigators with consultative support in biostatistics, and 2) support computer-based communication and database needs. Activities supported will include: network development and maintenance, participation in study design and statistical analysis of biomarker data, involvement in epidemiological design and analysis of complex databases, and contribution to large-scale mathematical modeling of exposure and remediation processes using main-frame computers. These services will greatly enhance the ability of all components of the Superfund program to achieve three specific aims.